This study evaluates the association between consultant and hospital volume and the risk of re-revision and 90-day mortality following first-time revision of primary hip replacement for aseptic loosening.

We conducted a cohort study of first-time, single-stage revision hip replacements (RHR) performed for aseptic loosening and recorded in the National Joint Registry (NJR) data for England, Wales, Northern Ireland, and the Isle of Man between 2003 and 2019. Patient identifiers were used to link records to national mortality data, and to NJR data to identify subsequent re-revision procedures. Multivariable Cox proportional hazard models with restricted cubic splines were used to define associations between volume and outcome.

Among 12,676 RHR there were 513 re-revisions within two years, and 95 deaths within 90 days of surgery. The risk of re-revision was highest for a consultant's first RHR (Hazard Ratio (HR) 1·58 (95%CI 1·16 to 2·15)) and remained significantly elevated for their first 26 cases (HR 1·26 (95%CI 1·00 to 1·58)). Annual consultant volumes of five/year were associated with an almost 30% greater risk of re-revision (HR 1·28 (95%CI 1·00 to 1·64)) and 80% greater risk of 90-day mortality (HR 1·81 (95%CI 1·02 to 3·21)) compared to volumes of 20/year. RHR performed at hospitals which had cumulatively undertaken fewer than 168 RHR were at up to 70% greater risk of re-revision (HR 1·70 (95% CI 1·12 to 2·60)), and those having undertaken fewer than 309 RHR were at up to three times greater risk of 90-day mortality (HR 3·06 (95% CI 1·19 to 7·86)).

This study found a significantly higher risk of re-revision and early postoperative mortality following first-time single-stage RHR for aseptic loosening when performed by lower-volume consultants and at lower-volume institutions, supporting the move towards the centralisation of such cases towards higher-volume units and surgeons.

Aims

This study describes the variation in the annual volumes of revision hip arthroplasty (RHA) undertaken by consultant surgeons nationally, and the rate of accrual of RHA and corresponding primary hip arthroplasty (PHA) volume for new consultants entering practice.

Total hip replacement (THR) for end-stage osteoarthritis is a commonly performed cost-effective procedure, which provides patients with significant clinical improvement. Estimating the future demand for joint replacement is important to identify the healthcare resources needed. We estimated the number of primary THRs that will need to be performed up to the year 2060.

We used data from The National Joint Registry for England, Wales, Northern Ireland and the Isle of Man on the current volume of primary THR (n=94,936) performed in 2018. We projected future numbers of THR using a static estimated rate from 2018 applied to population growth forecast data from the UK Office for National Statistics up to 2060.

By 2060, primary THR volume would increase from 2018 levels by an estimated 37.7% (n=130,766). For both males and females demand for surgery was also higher for patients aged 70 and over, with older patients having the biggest relative increase in volume over time: 70–79 years (144.6% males, 141.2% females); 80–89 years (212.4% males, 185.6% females); 90 years and older (448.0% males, 298.2% females).

By 2060 demand for THR is estimated to increase by almost 40%. Demand will be greatest in older patients (70 years+), which will have significant implications for the health service that requires forward planning given morbidity and resource use is higher in this population. There is a backlog of current demand with cancellation of elective surgery due to seasonal flu pressures in 2017 and now Covid-19 in 2020. Orthopaedics already has the largest waiting list of any speciality. These issues will negatively impact the health services ability to deliver timely joint replacement to many patients for a number of years and require urgent planning.

Follow-up of arthroplasty varies widely across the UK. The aim of this NIHR-funded study was to employ a mixed-methods approach to examine the requirements for arthroplasty follow-up and produce evidence-based and consensus-based recommendations. It has been supported by BHS, BASK, BOA, ODEP and NJR.

Four interconnected work packages have recently been completed: (1) a systematic literature review; (2a) analysis of routinely collected National Health Service data from four national data sets to understand when and which patients present for revision surgery; (2b) prospective data regarding how patients currently present for revision surgery; (3) economic modelling to simulate long-term costs and quality-adjusted life years associated with different follow-up care models and (4) a Delphi-consensus process, involving all stakeholders, to develop a policy document to guide appropriate follow-up care after primary hip and knee arthroplasty.

We will present the following Recommendations:

For ODEP10A∗ minimum implants, it is safe to disinvest in routine follow-up from 1 to 10 years post non-complex hip and knee replacement provided there is rapid access to orthopaedic review

Background

Few studies have compared aspirin with DOACs (direct oral anticoagulants = direct thrombin inhibitors and factor Xa inhibitors) for venous thromboembolism (VTE) prophylaxis following total hip and knee replacement (THR and TKR). We assessed the efficacy and safety of aspirin compared with DOACs for VTE prophylaxis following THR and TKR using the world's largest joint replacement registry.

Aims

We compared implant and patient survival following intraoperative periprosthetic femoral fractures (IOPFFs) during primary total hip arthroplasty (THA) with matched controls.

Introduction

We investigated predictors of poor outcomes following metal-on-metal hip arthroplasty (MoMHA) revision surgery performed for adverse reactions to metal debris (ARMD), to help inform the revision threshold and type of reconstruction.

Introduction

Smoking, a modifiable factor, may adversely affect post-operative outcomes. Healthcare providers are increasingly denying smokers access to total hip arthroplasty (THA) until they stop smoking. Evidence supporting this is unclear. We assessed the effect of smoking on outcomes following THA.

Introduction

Total hip arthroplasty (THA) is indicated in independently mobile patients sustaining displaced intracapsular hip fractures. Studies presently suggest that the anterolateral approach is preferable to the posterior approach due to a perceived reduced risk of reoperations and dislocations. However, these observations come from small studies with short follow-up. We assessed whether surgical approach in THA performed for hip fractures effects outcomes.

Introduction

Intraoperative periprosthetic femoral fractures (IOPFF) lead to reduced implant survival. A deeper understanding of predictors enables surgeons to modify techniques and patient selection to reduce the risk of IOPFF. The aim of this study was to estimate predictors of IOPFF and each anatomical subtype (calcar crack, trochanteric fracture, femoral shaft fracture) during primary THA.

Pseudotumours have recently been reported in non-metal-on-metal total hip replacements (non-MoM THRs), however the magnitude and risk factors for this complication are unknown, as is the outcome of its treatment.

3340 primary THR undergoing revision for pseudotumour between 2008 and 2015 were identified in the National Joint Registry for England and Wales. 7.5% (n=249) of these pseudotumour revisions, had non-MoM bearing surfaces. The risk of revision for pseudotumour in non-MoM hips was 0.032% (249/789,397; 95% CI 0.028%–0.036%). The risk of pseudotumour revision was 2.35 times (95% CI 1.76–3.11) higher in ceramic-on-ceramic compared with hard-on-soft bearings, and 2.80 times (95% CI 1.74–4.36) higher in 36mm metal-on-polyethylene bearings compared to 28mm and 32mm metal-on-polyethylene bearings.

The outcome of revision for pseudotumour non-MoM hips was studied in 185 hips. 13.5% (n=25) had re-revisions at a mean of 1.2 years (range 0.1–3.1 years). Infection (32%), dislocation/subluxation (24%), and aseptic loosening (24%) were the commonest indications for re-revision. The 4-year survival rate was 83.8% (95% CI=76.7%–88.9%). Multiple revision indications (Hazard Ratio (HR)=2.78; 95% CI=1.03–7.49) and incomplete revision procedures (HR=5.76; 95% CI=1.28–25.9) increased the risk of re-revision

Although the overall risk of revision for pseudotumour in non-MoM THRs is low, the risk is increasing and is significantly higher in ceramic-on-ceramic and large head metal-on-polyethylene THR. These revisions have a high early failure rate.

Aims

The aim of this study was to determine whether the rates of revision for metal-on-metal (MoM) total hip arthroplasties (THAs) with Pinnacle components varied according to the year of the initial operation, and compare these with the rates of revision for other designs of MoM THA.

Aims

To determine the outcomes following revision surgery of metal-on-metal hip arthroplasties (MoMHA) performed for adverse reactions to metal debris (ARMD), and to identify factors predictive of re-revision.

Objectives

Few studies have assessed outcomes following non-metal-on-metal hip arthroplasty (non-MoMHA) revision surgery performed for adverse reactions to metal debris (ARMD). We assessed outcomes following non-MoMHA revision surgery performed for ARMD, and identified predictors of re-revision.

Outcomes following metal-on-metal hip replacement (MoMHR) revision surgery for adverse reactions to metal debris (ARMD) have been poor, and inferior compared with non-ARMD revisions. Subsequently, surgeons and worldwide authorities widely recommended early revision for ARMD, with a lower surgical threshold adopted. However, the impact of early surgery for ARMD is unknown. We compared the rates of adverse outcomes following MoMHR revision surgery in matched ARMD and non-ARMD patients.

We performed a retrospective observational study using data from the National Joint Registry for England, Wales, Northern Ireland and the Isle of Man. All MoMHR patients subsequently undergoing revision surgery for any indication between August 2008 and August 2014 were eligible. ARMD and non-ARMD revisions were matched one-to-one for multiple potential confounding factors using propensity scores. Adverse outcomes following revision surgery (intra-operative complications, mortality, re-revision surgery) were compared between matched groups using regression analysis.

In 2,576 matched MoMHR revisions (ARMD=1,288 and non-ARMD=1,288), intra-operative complications were similar between ARMD (2.4%) and non-ARMD (2.5%) revisions (odds ratio=0.97, 95% CI=0.59–1.60; p=0.899). All-cause mortality rates were lower following ARMD revision compared with non-ARMD revision (hazard ratio (HR)=0.43, 95% CI=0.22–0.86; p=0.018). All-cause re-revision rates were lower following ARMD revision compared with non-ARMD revision (HR=0.52, 95% CI=0.36–0.75; p<0.001). Compared with ARMD revision (5-years=94.3%), MoMHR revisions for infection (5-years=81.2%) and dislocation/subluxation (5-years=81.9%) had the lowest implant survival rates.

Contrary to previous observations, MoMHRs revised for ARMD have approximately half the risk of re-revision and death compared to non-ARMD revisions. We suspect worldwide regulatory authorities have positively influenced outcomes following ARMD revision by widely recommending that surgeons exercise a lower revision threshold.

Our findings suggest the threshold for ARMD revision surgery need not be lowered further. The high risk of failure following MoMHR revision for infection and dislocation is concerning.

Recent studies have demonstrated that implant-specific blood metal ion thresholds exist in unilateral and bilateral metal-on-metal (MoM) hip arthroplasty patients, with these thresholds being most effective for identifying patients at low-risk of adverse reactions to metal debris (ARMD). We investigated whether these new blood metal ion thresholds could effectively identify patients at risk of ARMD in an external cohort of MoM hip arthroplasty patients.

We performed a validation study involving 803 MoM hip arthroplasties implanted in 710 patients at three European centres (323=unilateral Birmingham Hip Resurfacing (BHR); 93=bilateral BHR; 294=unilateral Corail-Pinnacle). All patients underwent whole blood metal ion sampling. Patients were divided into those with ARMD (revised for ARMD or ARMD on imaging; n=75), and those without ARMD (n=635). Previously devised implant-specific blood metal ion thresholds (cobalt=2.15μg/l for unilateral BHR; maximum cobalt or chromium=5.5μg/l for bilateral BHR; cobalt=3.57μg/l for unilateral Corail-Pinnacle) were applied to the validation cohort, with receiver operating characteristic curve analysis used to establish the discriminatory characteristics for each respective threshold.

The area under the curve, sensitivity, specificity, positive predictive value and negative predictive value for distinguishing between patients with and without ARMD for each implant-specific threshold were respectively: unilateral BHR=89.4% (95% CI=82.8%-96.0%), 78.9%, 86.7%, 44.1%, 96.9%; bilateral BHR=89.2% (95% CI=81.3%-97.1%), 70.6%, 86.8%, 54.5%, 93.0%; unilateral Corail-Pinnacle=76.9% (95% CI=63.9%-90.0%), 65.0%, 85.4%, 24.5%, 97.1%. The 7μg/l UK MHRA threshold missed significantly more patients with ARMD compared with the implant-specific thresholds (4.9% vs. 2.8%; p=0.0003).

This external multi-centre validation study has confirmed that MoM hip arthroplasty patients with blood metal ion levels below newly devised implant-specific thresholds have a low-risk of ARMD. Compared to implant-specific thresholds, the currently proposed fixed MHRA threshold missed more patients with ARMD.

We recommend using implant-specific thresholds over fixed thresholds when managing MoM hip arthroplasty patients.

Recent studies have reported on non-metal-on-metal hip arthroplasty (non-MoMHA) patients requiring revision surgery for adverse reactions to metal debris (ARMD). Although the outcomes following revision surgery for ARMD in MoMHA patients are known to generally be poor, little evidence exists regarding outcomes following non-MoMHA revision surgery performed for ARMD. We determined the outcomes following non-MoMHA revision surgery performed for ARMD, and identified predictors of re-revision.

We performed a retrospective observational study using data from the National Joint Registry for England, Wales, Northern Ireland and the Isle of Man. All primary non-MoMHA patients who subsequently underwent revision surgery for ARMD between 2008–2014 were included (n=185). Outcome measures following ARMD revision were intraoperative complications, mortality, and re-revision surgery. Predictors of re-revision surgery were identified using Cox regression analysis.

Intra-operative complications occurred in 6.0% (n=11) of ARMD revisions. The cumulative 4-year patient survival rate was 98.2% (95% CI=92.9–99.5%). Re-revision surgery was performed in 13.5% (n=25) of hips at a mean time of 1.2 years (range 0.1–3.1 years) following ARMD revision. Infection (32%), dislocation/subluxation (24%), and aseptic loosening (24%) were the commonest re-revision indications. The cumulative 4-year implant survival rate was 83.8% (95% CI=76.7%-88.9%). Significant predictors of re-revision were: multiple revision indications (Hazard Ratio (HR)=2.78; 95% CI=1.03–7.49; p=0.043), incomplete revision procedures (including modular component exchange only) (HR=5.76; 95% CI=1.28–25.9; p=0.022), and ceramic-on-polyethylene revision bearings (HR=3.08; 95% CI=1.01–9.36; p=0.047).

Non-MoMHA patients undergoing ARMD revision have a high short-term risk of re-revision. Infection, dislocation/subluxation, and aseptic loosening were the commonest re-revision indications. Furthermore, important and potentially modifiable predictors of future re-revision were identified.

Although the poor prognostic factors identified require validation in future studies, our findings may be used to counsel patients about the risks associated with ARMD revision surgery, and guide decisions about the reconstructive procedure.

Aims

To determine ten-year failure rates following 36 mm metal-on-metal (MoM) Pinnacle total hip arthroplasty (THA), and identify predictors of failure.

Introduction

The impact of pseudotumours associated with metal-on-metal hip resurfacings (MoMHRs) within the second decade is unknown. We investigated: (1) the incidence and risk factors for all-cause and pseudotumour revision following MoMHR at 15-years follow-up, and (2) whether risk factors were gender specific.